2b:null 2c:["$","title",null,{"children":"Introduction to D3 | Cu | Observable"}] 31:T550,chart = { // // Specify the chart's dimensions. // const width = 500; // const height = 300; // const marginTop = 25; // const marginRight = 20; // const marginBottom = 35; // const marginLeft = 40; // // Prepare the scales for positional encoding. // const x = d3. scaleLinear() // .domain(d3.extent(cars, d => d.mpg) ).nice() // .range([0, width]); // const y = d3. scaleLinear() // .domain(d3. extent (cars, d => d.hp)) .nice() // .range ([height, 0]); // // Create the SVG container. // const svg = d3. create("svg") // .attr("width", width + marginLeft + marginRight) // .attr("height", height + marginTop + marginBottom); // const g = svg.append ("g") // .attr("transform", `translate(${marginLeft}, ${marginTop})`); // // Create the x-axis. // g.append ("g") // .attr("transform", `translate(0,${height})`) // .call(d3.axisBottom(x).ticks(width / 80)) // // Create the y-axis. // g.append ("g") // .call(d3.axisLeft(y)) // // Add a layer of dots. // g.append ("g") // .attr("stroke", "steelblue") // .attr("stroke-width", 1.5) // .attr("fill", "white") // .selectAll("circle") // .data (cars) // .join("circle") // .attr("cx", d => x(d.mpg)) // .attr("cy", d => y(d.hp)) // .attr("r", 3); return svg.node(); }32:T434,testYourKnowledge([ { title: 'D3', backText: [`D3 stands for data-driven documents. Essentially, it's the process of binding data to HTML tags so we can base attributes on data properties.`, `Though it sounds similar, D3 is not about 3D visualziations.`], question: "D3 stands for data-driven development", answer: false }, { title: 'SVG', backText: ['SVG (scalable vector graphics) are a common way to build images for the Web.', 'SVG works quite well with D3 given how D3 generates data-driven documents.'], question: 'SVG is a text-based open Web standard for generating images.', answer: true }, { title: 'Complexity', backText: [`D3 adds a lot of complexity to developing data visualizations, and is often a more difficult to use for basic chart forms.`, `Where D3 shines is when you get into features that can't be done with other frameworks, like bespoke data visualization forms, animation and interactivity.`], question: `D3 is often the simplest way to make a bar chart or scatterplot.`, answer: false }, ], 300, 300)33:[] 2f:{"id":"3636d4a785ecbb99","slug":null,"title":"Introduction to D3","thumbnail":"d45ae9789b514f70deb5c6a5e451e9ce830bf507dd246adb4a623b386fbdf947","access_level":"public","create_time":"$D2025-09-24T02:01:02.710Z","update_time":"$D2025-09-24T02:01:02.710Z","view_time":null,"first_public_time":"$D2025-09-24T02:01:02.710Z","fork":{"id":"4c1d88420f35f3e3","slug":"introduction-to-d3","title":"Introduction to D3","owner":{"id":"d0e7d5042fb40aef","login":"cityu","name":"SM6351"}},"stars":0,"starred":false,"owner":{"type":"team","id":"2e5bfe0ce6ce7549","login":"cu3","name":"Cu","avatar_url":"https://avatars-next.observableusercontent.com/9a975e6775bd901b7adc4d6c6bba2701ad77e8686ac470ab38928697c9dd54b6","tier":"starter_2024"},"version":488,"publish_version":null,"role":null,"authored":false,"authors":[{"type":"individual","id":"45ee98670b70a40c","login":"lyan2","name":"Lyan","avatar_url":"https://avatars-next.observableusercontent.com/b21004147f9173553f17632b2395e7700828284262248816db713560d2687214","tier":null}],"members":[{"type":"individual","id":"45ee98670b70a40c","login":"lyan2","name":"Lyan","avatar_url":"https://avatars-next.observableusercontent.com/b21004147f9173553f17632b2395e7700828284262248816db713560d2687214","tier":null,"role":"editor"}],"comments":[],"custom_thumbnail":false,"trashed":false,"lapsed":null,"subscribed":null,"forks":1,"collection":null,"type":"notebook","body":{"title":"Introduction to D3","cells":[{"id":0,"value":"# Introduction to D3 \n## D3 & Web-Based Data Visualization","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":43,"value":"[Session 1 slide deck](https://docs.google.com/presentation/d/19fr5Wb0I4xitkFffP0FSX0s1Z4GUbrtUojZHcA9B_WE/edit?usp=sharing)","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":33,"value":"---\n## Activity 1\n
","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":34,"value":"### Observable Setup\n1. Sign-in / Sign-up\n2. Fork this notebook\n4. Edit and run the cell below\n5. Hide the code using the pin icon\n6. Create a new JavaScript cell\n7. Write `a = 10`\n8. Duplicate the cell, change the code to `b = a * 2`\n9. Open the Minimap pane\n\n_For more, check out [A Taste of Observable](https://observablehq.com/@observablehq/a-taste-of-observable?collection=%40observablehq%2Fgetting-started)_","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":46,"value":"

Hello, Typhoon!

","pinned":false,"hidden":false,"mode":"html","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":473,"value":"a = {\n const a = 10;\n const b = a*a+10-9;\n return a;\n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":485,"value":"b = a*a;","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":35,"value":"note(md`__Note:__ You can run a cell by clicking on the play button to the right of the code, or using Shift + Enter`)","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":84,"value":"---\n## Activity 2\n
","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":126,"value":"### Writing HTML and CSS\n- Add a `

` tag to this code below with a nested `

` tag, which contains the text \"Whoa, I'm writing HTML!\"\n- Update the CSS at the top to change the font color to red.\n- Update the CSS to make just the H3 in the code below blue.\n\n\n_For more, check out [Code Academy HTML & CSS](https://www.codecademy.com/catalog/language/html-css)_","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":117,"value":"\n\n

HTML is neat!

It's what all your websites are built in at the end of the day.

HTML is

Fun
Cool
Old

","pinned":true,"hidden":false,"mode":"html","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":209,"value":"htl.html`

You can write also write HTML in a JavaScript cell using htl.html! We'll do this often for D3 examples, since we're working with JavaScript when writing D3.

`","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":90,"value":"---\n## Activity 3\n
","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":169,"value":"### Writing JavaScript\n- Create an array of 1, 2, 3, 4\n- Use the map method on that array to double each number, employing\n- Filter the array based on the index being greater than 2\n\n_For a more in-depth walkthrough of JavaScript Fundamentals check out [Learn Just Enough JavaScript](https://observablehq.com/@observablehq/learn-javascript-introduction?collection=%40observablehq%2Ftutorial)_","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":175,"value":"myCellArray = {\n \n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":91,"value":"---\n## Activity 4\n
","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":182,"value":"### Understanding the SVG & DOM\n- Change values in the Chart cell dropdown and see how it changes the structure of the DOM.\n- Look at the hiearchy of values and try to predict which is what.\n- Use the `inspect` option to open your JavaScript console and view that way as well.","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":189,"value":"myChart = Plot.plot({\n marks: [\n Plot.auto(carsData, {x: \"power (hp)\", y: \"weight (lb)\", color: \"#666666\"})\n ]\n})","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"myChart","database":"$undefined"},{"id":193,"value":"{\n const label = d => d.data.node\n const root = stratifyTree(getDOMTree(myChart))\n return graph(root, {label: label})\n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":92,"value":"---\n## Activity 5\n
","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":186,"value":"### D3 first steps\n- Use D3 select to select the `

` tags\n- Bind the array `[1, 2, 3]` to the `

` tags and use that to change the text\n- Inspect a `

` tag to see the data bound using in the JavaScript console `$0.__data__`\n- Use `.style()` to set a custom style\n- Filter based on index","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":230,"value":"{\n const html = htl.html`

First Paragraph

Second Paragraph

Third Paragraph

`;\n\n return html;\n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":283,"value":"note(md`__Note:__ D3 is part of our standard library, so we don't need to install it here. We're using D3 version ${d3.version}`)","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":417,"value":"---\n## Activity 6\n
","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":421,"value":"### Data Loading\n- Define the dimensions for the chart\n- Specify the domain and range for the x and y scale\n- Create our SVG container, which is what we’ll return in the end\n- Create subcontainers and axes components\n- Create the circles for the scatterplot, using the container and scales defined before.","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":435,"value":"$31","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":50,"value":"---\n## Wrap Up\nTest your knowledge from session one with these short questions.","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":28,"value":"$32","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":275,"value":"

","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":277,"value":"

","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":278,"value":"

","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":280,"value":"

","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":13,"value":"---\n## Appendix","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":14,"value":"import {note} from \"@observablehq/callout-boxes\"","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":15,"value":"import { showMe } from \"@observablehq/show-me\"","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":16,"value":"import {testYourKnowledge} from \"@observablehq/test-your-knowledge-cards\"","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":128,"value":"import {stratifyTree, getDOMTree, graph} from \"@pstuffa/svg-to-dom-tree\"","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":17,"value":"color = d3.schemeBlues[7]","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":146,"value":"carsData = cars","pinned":true,"hidden":true,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"carsData","database":"$undefined"}],"files":"$W33","stdlib":"1","titling":"auto"}} 30:"$2f:body"